Construction of the eukaryotic coexpression vector containing Mycobacterium tuberculosis heat shock protein 70 and green fluorescent protein / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct an eukaryotic coexpression vector containing Mycobacterium tuberculosis heat shock protein 70 (mtHSP70) and enhanced green fluorescent protein (EGFP) controlled by cytomegalovirus promoter using pIRES-EGFP vector.</p><p><b>METHODS</b>The mtHSP70 gene fragment was amplified by PCR from pVAX-mtHSP70-HSV2gD using specific primers. The PCR product was cloned into the vector pMD 18-T vector, and the correct clone was selected according to DNA sequence analysis. The interested mtHSP70 gene fragment was subcloned into pCMV-IRES-EGFP vector with XhoI and EcoR I digestion. The recombinant plasmid was transfected into mouse melanoma B16 cell line, and the green fluorescent cells were detected by fluorescence microscopy and mtHSP70 expression was detected by Western blotting.</p><p><b>RESULTS</b>The recombinant plasmid obtained was confirmed by enzyme digestion. The transfected mouse melanoma B16 cells exhibited green fluorescence under fluorescence microscopy and expressed mtHSP70 protein as demonstrated by Western blotting.</p><p><b>CONCLUSION</b>The eukaryotic coexpression vector PCMV-mtHSP70-IRES-EGFP has been established to allow further investigation of the role of mtHSP70 gene in tumor immunotherapy.</p>

Culture and identify the human umbilical vein endothelial cells and investigate the expression of tyrosine kinase-2 with immunoglobulin-like and epidermal growth factor homology domains in the cells / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the cultural method and identification of human umbilical vein endothelial cells (HUVECs), and investigate the expression of tyrosine kinase-2 with immunoglobulin-like and epidermal growth factor homology domains(Tie-2) in HUVECs.</p><p><b>METHODS</b>HUVECs were isolated from umbilical veins by the technique of irrigative digestion, and were cultivated in plates. The cells were identified by VIII monoclonal antibody. Tie-2 mRNA and protein were detected by reverse transcription-polymerase chain reaction (RT-PCR) and SABC immunocytochemistry.</p><p><b>RESULTS</b>HUVECs could adhere to the plates completely after 24 hours, and confluence a monolayer 4-5 days later. The band of Tie-2 mRNA was obviously and the expression of Tie-2 protein was strongly positive by immunocytochemistry in HUVECs. The positive rate was over 85%.</p><p><b>CONCLUSION</b>Highly purified endothelial cells were isolated. And there were overexpression of Tie-2 in HUVECs.</p>

Effect of vascular endothelial growth factor 165 gene transfection on bone defects and its mRNA expression in rabbits / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Gene therapy has been a hot spot in repair of bone defects in recent years. This study aimed to construct a recombinant plasmid pcDNA3.1-VEGF(165), and to observe the effect of vascular endothelial growth factor 165 (VEGF(165)) gene therapy on bone defects in rabbits.</p><p><b>METHODS</b>Total RNA was extracted from rabbit bone tissues. VEGF(165) cDNA fragment was prepared by reverse transcription and the gene was cloned by polymerase chain reaction (PCR). Plasmid pMD18-T/VEGF(165) combined with pcDNA3.1 was cloned to reconstruct pcDNA3.1-VEGF(165) plasmid. Thirty New Zealand white rabbits weighing (2.50 +/- 0.13) kg were used to establish models of bone defects (1 cm in length) of the bilateral radii. The bone defects were repaired with absorbable gelatin sponge. After the operation, physiological sodium chloride solution was injected into the injured site in one of the forelegs of the rabbits as the control group, and pcDNA3.1-VEGF(165) plasmid (0.2 ml, 200 ng) was injected into the opposite foreleg as the experiment groups. At weeks 1, 2, 4, 6, 8, and 12 after the treatments, the bones were examined by X-ray, and the specimens of the bone defects were collected, stained with HE, and observed under a light microscope. The expression of VEGF(165) mRNA was examined by real-time quantitative polymerase chain reaction (RQ-PCR).</p><p><b>RESULTS</b>The pcDNA3.1-VEGF(165) plasmid with a correct sequence was constructed successfully. Postoperative X-ray found no difference between the two groups at week 1. In the experiment group, callus and synostosis were observed after 2 weeks, and osteosis structure was normal at week 12; these phenomena occurred much later in the control group. In the experiment group, HE staining showed a large amount of newly formed blood vessels after 2 weeks, a number of bone trabeculae with osteoblasts proliferation at 4 weeks, and fresh bone cortex and reformed medullary cavity at 12 weeks; whereas in the control group these structures formed in later phases. The VEGF(165) mRNA in the experiment group was expressed at a low level at week 1, reached the peak at weeks 3, and then decreased to a normal level after 6 weeks.</p><p><b>CONCLUSIONS</b>Local use of pcDNA3.1-VEGF(165) plasmid at bone defects can upregulate the expression of VEGF(165) and accelerate the formation of capillaries and the repair of bone defects. Angiogenesis and osteogenesis can be promoted by a combination of pcDNA3.1-VEGF(165) and gelatin sponge.</p>

The effect of pcDNA3.1-vEGF165 recombined vector on wound healing and the expression of collagen type I, III mRNA in wounded tissue / 中华整形外科杂志

<p><b>OBJECTIVE</b>To examine the effect of pcDNA3.1-VEGF165 vector to the angiogoiesis, expression of collagen type I and type III mRNA in soft tissue injury model.</p><p><b>METHODS</b>Thirty two Sprague-Daulay rats,weighted (180 +/- 20) g, were made tissue injury in the bilateral of vertebral region. Round wound (diameter 12 mm) was made by perforex on the back, removed the skin and 2 mm muscle, one side was experimental group by random and the other as control. The wound was done with sodium chloride (0.2 ml) in the control group, with the recombinant VEGF165 vector (0.2 ml, 200 mg) in the experimental group. The wound healing and other general state of health was observed after the operation. The specimens were obtained at 3,5, 7,14 and 30 days after injury. Draw the materials from the rats at the same time, all samples were divided into two parts. one ( > 0.1 g) was conserved in refrigerator at - 80 degrees C, which was extracted total RNA by TRIZOL, design the primer of rat's collagen type I and type III, RT-PCR analysis indicated that collagen type I, III. The other was fixed by 10% formalin. Examine wound healing of local tissue and count it' s MVD by HE staining.</p><p><b>RESULTS</b>All the rabbits were well alive, no death or infection. Wound healing time was shorter than the control one (14.2, 17.4 d). Inflammatory cell infiltrate, cellula intersitialis, fibroblast, collagen and the density of angiogenesis were more in the experimental group than in the control one. The MVD was significant difference between the two groups at 1, 2 weeks are 63.38 +/- 9.20, 52.72 +/- 7.06 and 76.64 +/- 12.27, 66.84 +/- 9.82 (P < 0.05). The expression of collagen type I , III mRNA was found in the third day, the peak was in the second week and then degression. The collagen type I , III mRNA and beta-actin specificitic belt were found and its initial template volume different, the results was trend of RT-PCR obtained.</p><p><b>CONCLUSIONS</b>The local application of pcDNA3.1-VEGF165 can enhance the expression of collagen type I, III mRNA, enhance angiogenesis and extra cellular matrix, both of which can shorten healing time of tissue injury.</p>